1. Field of the Invention
The present invention relates to a technique for presenting content items to a user.
2. Description of the Related Art
A conventional technique is known in which when a user is, for example, producing a document, support is provided to the user for locating required information. For example, there is a categorization technique in which content items having similar features are automatically grouped, thereby facilitating location of desired content items (documents, images and the like) on behalf of the user. As one of the methods for categorizing content items, there is a method in which characteristic amounts indicating the features of content items are extracted, and content items having similar characteristic amounts are grouped. However, with such a categorization method, it may be difficult to determine what feature each content group has. According to the technique disclosed in Japanese Patent Laid-Open No. 2009-251825, keywords are extracted from documents, and the documents are categorized according to the positions of the keywords in the thesaurus.
When a user creates a project proposal for a new project, information or content items that the user needs may be unknown or unfamiliar to the user. In such a case, it is desirable to categorize content items such that the user can find necessary content. However, even if a conventional technique in which content items having similar features are grouped is used, for example, it is difficult to anticipate under what topic the content items have been grouped. When the user is searching for a content item in a field unknown to him or her, the user may not know which content group to search.
With the technique that uses a thesaurus, documents are mapped onto the thesaurus. Accordingly, it is easy to anticipate what feature each content group has. However, with this technique, when documents in an unknown field are searched, it is necessary to determine whether each document corresponds to important information or not, with looking through the thesaurus.